The anatomy is a bit off on the wolf. From the looks of it you had reference material. Sometimes, the reference material can't be taken so literally, unless you are going for hyper realism in which case the reference needs to be followed meticulously, in which case using a grid on both the reference and the work can do wonders.

BUT in the off-chance you didn't use any reference and I'm looking like an idiot... an example would be the mouth edges not receding far enough towards the dogs jaw. Dogs/wolfs have jowls that have trouble puckering (for lack of better word) up like this guy here.

The focal point of the piece is thrown off by the wolf being so light. Something simple like thickening the lines on the wolf towards where you'd like the focal point can add an illusion of polish to the piece. The range of greys used on the wolf are quite limited, keep in mind one piece can go from the whitest white to the blackest black.

The wolf does have some good bits though, the neck/throat scruff in particular has a good sense of depth/layers to it.

BUT, enough of the wolf. I only focused on it so much because the other half of the piece is quite strong. The colors are blended in a very interesting way that pulls the viewers eye to several sides of the breath. The page white was utilized as part of it as well, it doesn't seem as if you left a hold in the breath at all even though you did.

It's great how not even the outline stays the same color, it can be really easy to get in the habit of making lines generic.

All in all, this is definitely a GOOD piece. Traditional mediums are tricky, there is no undo, so confidence in your work can often lead to positive results, and even some happy mistakes.